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Solar System 2010. Presented by Linder Winter. EVENT DESCRIPTION. This event will address: The Sun Planets and their satellites Dwarf planets Comets Asteroids and the asteroid belt Meteoroids Oort Cloud Kuiper Belt. EVENT DESCRIPTION. A TEAM OF UP TO : 2
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Solar System 2010 Presented by Linder Winter
EVENT DESCRIPTION This event will address: • The Sun • Planets and their satellites • Dwarf planets • Comets • Asteroids and the asteroid belt • Meteoroids • Oort Cloud • Kuiper Belt
EVENT DESCRIPTION A TEAM OF UP TO: 2 APPROXIMATE TIME: 50 Minutes
EVENT PARAMETERS Teams may bring only one 8.5” x 11” two-sided sheet of notes containing images, graphics and text, plus a basic, non-programmable calculator with a square root function.
THE COMPETITION Participants will be presented with one or more tasks, each requiring the use of one or more process skills. Skills may include, but are not limited to, generating inferences, making predictions, problem solving, making and recording observations, formulating and evaluating hypotheses, interpreting data and graphing. The exam may be presented using a thematic approach.
KNOWLEDGE vs.CONCEPTUALLY-BASED LEARNING Knowledge: Basic information often included in notes for quick reference. Conceptual: Application of “basic knowledge” to tasks requiring reasoning. Ideally, Science Olympiad activities move from basic knowledge at invitational and regional competitions to more challenging conceptual activities at state and national competitions.
KNOWLEDGE vs.CONCEPTUALLY-BASED LEARNING • Student notes should be a collection of basic knowledge and facts. These may include tables, graphs and graphics. • Preparation for competitions should include numerous opportunities for participants to develop conceptual thinking skills. • During this presentation, numerous examples of conceptual activities will be suggested for use in preparing for competitions.
KNOWLEDGE vs.CONCEPTUALLY-BASED LEARNING • In preparing your team, select relevant images, graphs, charts, tables, etc. and challenge participants to use these in developing their own lists of questions, tasks and activities. • Providing opportunities to develop sound conceptual thinking skills is the most effective type of preparation for SO competitions.
KNOWLEDGE vs.CONCEPTUALLY-BASED LEARNING • Caution participants that the supervisor who actually writes the exam may be a fact-oriented person, so you must prepare them for this possibility also! • Even if the supervisor happens to be a fact-oriented individual, participants who have experienced conceptual learning will have an edge on those whose preparation was primarily based on memorization of facts.
Topics of Study • Each of the topics included in the Solar System event will be introduced in the next series of slides. • This series of slides may be used to introduce the event to students who have expressed a desire to participate in this event.
History and Formation of the Solar System • Much of our know-ledge of how the solar system was formed is gained from direct observations of objects within other galaxies and solar systems – both younger and older. Image: Northrop Grumman Corporation
History and Formation of the Solar System • The planets of the Solar System formed from a nebula of gas, dust, and ices coalescing into a dusty disk around the evolving Sun. • Within the disk, tiny dust grains and ices coagulated into growing bodies called planetesimals. Image: Pat Rawlings, NASA
Objects of the Solar System: Sun • Prominences are dense clouds of material suspended above the surface of the Sun by loops of magnetic field. • Prominences and filaments are actually the same objects, except that promi-nences are seen projecting out above the limb of the Sun.
Objects of the Solar System: Sun • Spicules are small, jet-like eruptions. • Spicules appear as short dark streaks. • Although spicules last just a few minutes they eject material off of the surface and outward into the hot corona at speeds of 20 to 30 km/s.
Objects of the Solar System: Sun • Solar flares are tremendous explosions on the surface of the Sun. • Solar flares occur near sunspots between areas of oppositely directed magnetic fields.
Objects of the Solar System: Sun • Coronal Mass Ejections or (CMEs) are huge bubbles of gas threaded with magnetic field lines that are ejected from the Sun over the course of several hours.
Objects of the Solar System: Sun • Coronal Mass Ejections disrupt the flow of the solar wind and produce disturbances that strike the Earth with sometimes catastrophic results.
Objects of the Solar System: Sun • Coronal mass ejections are often associated with solar flares and prominence eruptions but they can also occur in the absence of either of these processes.
Objects of the Solar System: Sun • The Sun's core is the central region where nuclear reactions consume hydrogen to form helium. • These reactions release the energy that ultimately leaves the surface as visible light.
Objects of the Solar System: Sun • The radiative zone extends outward from the outer edge of the core to the interface. • The radiative zone is characterized by its method of energy transport - radiation. • Energy generated in the core is carried by light that bounces from particle to particle through the radiative zone.
Objects of the Solar System: Sun • The interface layer lies between the radiative zone and the convective zone. • The fluid motions found in the convec-tion zone slowly disappear from the top of this layer to its bottom where the conditions match those of the calm radiative zone.
Objects of the Solar System: Sun • It is now believed that the Sun's magnetic field is generated by a magnetic dynamo in the interface layer. • Changes in fluid flow velocities across the layer can stretch magnetic field lines of force and make them stronger.
Objects of the Solar System: Sun • The convective zone is the outermost layer of the solar interior. • It extends from a depth of about 200,000 km right up to the visible surface. • Convective motions carry heat to the surface. • These motions are visible at the surface as granules and super-granules.
Objects of the Solar System: Planets According to the International Astronomical Union (IAU), a planet is a celestial body that: • Is in orbit around the Sun, • Has sufficient mass to assume a hydrostatic equilibrium (nearly round) shape, and • Has “cleared the neighbor-hood” around its orbit. • This definition does not apply outside the solar system. http://www.ccastronomy.org/tour_of_universe_tour.htm
Objects of the Solar System: Dwarf Planets According to the IAU, a dwarf planet: • Is in orbit around the Sun • Has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, • Has not “cleared the neighbor-hood” around its orbit, and • Is not a satellite of a planet, or other nonstellar body. http://www.ccastronomy.org/tour_of_universe_tour.htm
Objects of the Solar System: Dwarf Planets • There are currently five official dwarf planets. Pluto was demoted to dwarf planet status. Ceres, the largest asteroid in the main asteroid belt between Mars and Jupiter, was also declared a dwarf planet. Images courtesy of NASA, ESA, JPL, and A. Feild (STScI).
Objects of the Solar System: Dwarf Planets • The three other dwarf planets are Eris, Make-make and Haumea. • Pluto, Makemake and Haumea orbit the Sun on the frozen fringes of our Solar System in the Kuiper Belt. • Eris, a Trans-Neptunian Object, is located even further from the Sun. Images courtesy of NASA, ESA, JPL, and A. Feild (STScI).
Objects of the Solar System: Dwarf Planets • Haumea is a large Kuiper Belt Object (KBO). • It is an icy world that orbits far from the Sun on the frozen fringes of our Solar System. • Because it is so far away, Haumea takes 285 years to orbit the Sun once! • Haumea is usually a bit further from the Sun than Pluto. Images courtesy of NASA, ESA, JPL, and A. Feild (STScI).
Objects of the Solar System: Dwarf Planets • What, do you suppose, causes this dwarf planet’s strange shape? • Which arrow, red or blue, represents the object’s most likely spin axis? Explain. Images courtesy of NASA, ESA, JPL, and A. Feild (STScI).
Objects of the Solar System: Dwarf Planets • What, do you suppose, causes this dwarf planet’s strange shape? Its rapid rotation. • Which arrow, red or blue, represents the object’s most likely spin axis? Explain. Red. It bulges outward the most along this line. Images courtesy of NASA, ESA, JPL, and A. Feild (STScI).
Objects of the Solar System: Satellites • Planetary rings are thought to have been created when small moons collided with others, or ventured too close to their parent planet. • The resulting fragments gradually spread out into concentric orbits, breaking into ever smaller fragments through repeated collisions, eventually forming a ring system.
Objects of the Solar System: Planets Seasons • Extraterrestrial seasons are hardly noticeable on some planets (Venus), extreme on others (Uranus), and in some cases impossible to define (Mercury). • Planetary seasons result from two factors: (1) axial tilt (2) variable distance from the sun (orbital eccentricity)
Objects of the Solar System: Planets Climates • Effects of atmospheres • Composition • Density • Orbital eccentricity • Distance from the Sun • Rotational rate • Axial tilt • Presence of surface liquids • Planetary size • Albedo • Solar wind
Objects of the Solar System: Planets Tidal Effects • The gravity of Jupiter and its large moons yank Io every which way. • Io’s "solid ground" tides are more than five times as high as Earth’s highest ocean tides!
Objects of the Solar System: Asteroids • The heaviest concen-tration of asteroids is in a region lying between the orbits of Mars and Jupiter called the asteroid belt.
Objects of the Solar System: Asteroids • Some 7000 asteroids have been identified so far. • It is likely that the origin of the asteroid belt lies in the gravitational perturbation of Jupiter, which kept these planetisimals from coalescing into larger bodies. The figure above shows the asteroid Gaspra which was investigated by the Galileo spacecraft
Objects of the Solar System: Asteroids • Asteroid orbit distributions show evidence for Kirkwood Gaps, which are certain orbital radii within the asteroid belt for which there are few asteroids. • These gaps are associated with orbital radii that lead to orbital periods that are ratios of integer multiples of Jupiter's orbital radius. • They result from resonance interactions with Jupiter that tend to eject asteroids from such orbits. The Galileo spacecraft found a surprise when it flew by the asteroid Ida: Ida has a tiny moon, which has been named Dactyl! The small dot to the right of Ida is Dactyl.
Objects of the Solar System: Meteoroids • A meteoroid is matter revolving around the sun or any object in interplanetary space that is too small to be called an asteroid or a comet. • Unofficially the size limit for an asteroid has been set at 50 meters; anything smaller than that is simply called a meteoroid.
Objects of the Solar System: Comets Information participants should know about comets: • Composition: water, carbon dioxide, ammonia, and methane ices, with mixed-in dust • Origins of short-period vs. long-period comets • Parts: head, coma and tails: ion (gas) tail, dust tail • Why they glow: reflection of light and gases being excited by sunlight emitting electromagnetic radiation • Disturbances that cause comets to leave their home in the Kuiper belt or Oort Cloud … passing star, etc • Influence of Jovian planets on their orbits
Objects of the Solar System: Comets • The center of a comet's head is called its nucleus. • The nucleus is a few kilometers across and is surrounded by a diffuse, bright region called the coma that may be a million kilometers in diameter. The coma is formed from gas and dust ejected from the nucleus as it is heated by the Sun. • The coma is bright both because it reflects sunlight and because its gases are excited by sunlight and emit electromagnetic radiation.
Objects of the Solar System: Comets Short-period comets are the most common. They have only mildly elliptical orbits that carry them out to a region lying from Jupiter to beyond the orbit of Neptune. Illustrated: Location of Halley’s Comet in the year 2024
Facts about the Asteroid Belt • The total weight of all the asteroids in the asteroid belt is about 1/35th of that of our moon! • Ceres, the largest asteroid, is about 1/3 the total weight of all the asteroids! • Even though there are a lot of asteroids, the asteroid belt is mostly empty space. • Traveling through the asteroid belt in a space ship would not be very much like what you see in a science fiction film. • In addition to the belt asteroids, there are others based upon their location and orbit in the solar system: Apollo, Amors, Atons, Trojan and Centaurs.
Kuiper Belt • The Kuiper Belt is made up of millions of icy and rocky objects that orbit our Sun beyond the orbits of Neptune and Pluto. • Scientists think the gravity of big planets like Jupiter and Saturn swept all these icy leftovers out to the edge of our solar system. Missions to Kuiper Belt: New HorizonsAfter it flies past Pluto and Charon, New Horizons will head into the Kuiper Belt. It will be the first spacecraft to explore this mysterious region.
Oort Cloud • The Oort Cloud is an immense spherically-shaped cloud surround-ing our Solar System. • The vast distance of the Oort cloud is considered to be the outer edge of the Solar System. A diagram comparing the size of the Oort Cloud to the orbits of Uranus and Pluto.
Lunar Eclipse 1. Penumbral Lunar Eclipse: The Moon passes through Earth's penumbral shadow. This type of eclipse is difficult to detect. 2. Partial Lunar Eclipse: A portion of the Moon passes through Earth's umbral shadow. 3. Total Lunar Eclipse: The entire Moon passes through Earth's umbral shadow.
Solar Eclipses • A solar eclipse occurs when the moon passes in a direct line between the Earth and the Sun. • The moon's shadow travels over the Earth's surface and blocks out the Sun's light as seen from Earth. Image courtesy of NASA
Solar Eclipses • During a total solar eclipse the entire central portion of the Sun is blocked out. • During a total solar eclipse, the Sun's outer atmosphere, the corona, is visible. Image Courtesy of NASA
Solar Eclipses • If the penumbra passes over you, only part of the Sun's surface will be blocked out. • You will see a partial solar eclipse, and the sky may dim slightly depending upon how much of the Sun's disc is covered. Partial Solar Eclipse
Solar Eclipses • In some cases, the moon is far enough away in its orbit that the umbra never reaches the Earth at all. In this case, there is no region of totality, and what you see is an annular solar eclipse. • In an annular eclipse, only a small, ring-like sliver of light of the Sun’s disk is visible. ("annular" means "of a ring"). Annular Eclipse Courtesy of NASA